I'm new to CKII but feel I have a reasonably good grasp of the basic game mechanics having had a couple of practice starts and a good read of the forum and guides.
So I'm playing Sweden and have reached 1131, I've been steadily chipping away conquering the pagans and have also become king of Finland.
Next step I send 3000 men off to the crusade thinking to win a little prestige and glory but after getting my arse kicked I retreated what was left of my troops back onto their fleet and back home thinking that would be the end of it.
Well, next thing I know I'm awarded the Kingdom of Jerusalem and my demesne has suddenly expanded to 42!
So the question is guys what do you suggest I do with all these holdings, award a few to every vassal, or hand the kingdom to a son maybe, or make a few Dukes instead?
HELP!
There are many solutions to this, some people don't want to deal with it and suggest you grant the title to the Papacy. You can also simply give the kingdom to a vassal - grant it to your heir, for example, and he'll divvy up/administrate the holdings beneath him - and it'll eventually come back directly under your control when you become the heir.
What I like to do is grant each County in the Jerusalem kingdom to a different person and keep the county of Jerusalem, so I'm still the center of power in my realm there. I'll usually move my capital there too for the lifetime of my current king, and until my kingdom there is powerful enough to defend itself. Your home realm is probably powerful enough to support and defend itself, whereas you have -zero- local military presence in Jerusalem for at least 5 years, and in practice usually your military is basically zilch for 12-15 years, and very weak for close to 30. Moving your capital there lets you instantly mercenaries and start your retinues in Jerusalem to deal with threats you would normally deal with using your levies. Otherwise you have to pack everyone in boats and take months to sail down there.
As for who to make the lords of each province, follow whatever system you use for determining whether your counties will be run by Lord Mayors, Prince-Bishops, or Counts. There are advantages and disadvantages to each (that are basically irrelevant for decades til the conquered penalties wear off). But the reason you probably want to keep the individual vassals weak there is because once the penalties fall off, if you have like 1-2 vassals running all of the kingdom of Jerusalem, it'll be very easy for them to tell you to go stuff it when the core of your power is in Sweden. If they're small, petty county lords, it gives you time to add to your holdings and create a larger base of power there. With 1-2 vassals controlling most/all of it, it's also easy for them to be Stupid Disinterested AI if the Muslims come to take you back over, watching impassively and barely defending themselves while the Muslims conquer them, whereas if they're all Counts directly beneath you, you will have more direct control over your military there.